Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, -1), (-1, 1), (0, -1), (0, 1), (1, -1), (1, 0)}.
A151477
Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, -1), (-1, 1), (0, -1), (0, 1), (1, -1), (1, 0)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =10a(4) =35a(5) =138a(6) =566a(7) =2431a(8) =10780a(9) =49067a(10) =228355a(11) =1081997a(12) =5207905a(13) =25403962a(14) =125377203a(15) =625176432a(16) =3145870880a(17) =15959346050a(18) =81557403529a(19) =419547453308
External references
- oeis: A151477